Lobalobo

I do not know the current models, but, in selecting the right camera for snorkeling with kids my main selection criterias would be:
1) wrist strap to attach your camera on your wrist
2) sufficient depth rating. Some cameras go up to 15m without separate case, and many small point-and-shoots have inexpensive cases up to 40m. I would avoid cameras that are just "water proof" or rated to 3m or 5m.
3) wide angle lense
4) for shallow snorkeling (less than 3-5m?) you might not need any filters at all
5) a bright LCD screen and preferably a hood as well
6) short trigger delay preferred or you'll miss a lot of opportunities

This is great, thanks.  Hope you don't mind some followup questions.  Regarding your (1), do you recommend any particular wrist strap for attaching the camera at the wrist (which I assume does not include dangling as from a conventional strap)?  Regarding (3), how wide do you recommend (in 35mm equivalents), as the Oly has an optional wide-angle attachment lens rated for underwater (more than just 3m, I believe) and I wonder whether to purchase it? Regarding your (5), you mention not needing a filter, but would the filter hurt in many situations, and might it help on some shots?  Thanks.

I can't speak for the oly.

I've had adequate pix for snorkelling, with a panasonic ts2 and the ts4 is out now...

The seal has been no problem for me.  After each use in salt water, I just put it in a sink of fresh water, for a half hour, and operate all the controls, and it is still good to go, 1-2 years later.

In hawaii, in clear water, at shallow snorkeling depth, you will not even need a filter.  Though you  might like it below 10 feet, and especially on video, which is more difficult to correct the colors.

Thanks for the response.  My TS2 didn't leak either for about two years, but just started to, and seemingly not through the sealed doors: the lens and lcd become covered with internal condensation but the sealed compartments remained dry.  I would have updated with the TS4, but the online reviews report significant number of cases with leaking, less so the Oly TG-1.  I'll almost never go below 10 feet, as I doubt I can get that low and still compose a shot as I'm an inexperienced snorkeler.  So maybe the Oly is fine without a filter.  At least one site suggested a filter even for taking photos at the surface, though, on the theory that the water absorbs light horizontally as well as vertically (though less, of course because horizontally the absorption is in one direction only). What do you think?